Interim Guidance for Clinicians on the Prevention and Treatment of Swine-Origin Influenza Virus Infection in Young Children
April 28, 2009 7:00 PM ET
This document provides interim guidance for clinicians who are caring for young children with confirmed or suspected swine-origin influenza A (H1N1) virus infection.
Young children and swine-origin influenza virus (S-OIV)
Little is currently known about how this new S-OIV circulating in people may affect children. However, we know from seasonal influenza and past pandemics that young children, especially those younger than 5 years of age and children who have high risk medical conditions, are at increased risk of influenza-related complications.
Illnesses caused by influenza virus infection are difficult to distinguish from illnesses caused by other respiratory pathogens based on symptoms alone. Young children are less likely to have typical influenza symptoms (e.g., fever and cough) and infants may present to medical care with fever and lethargy, and may not have cough or other respiratory symptoms or signs.
Influenza-associated deaths among children, while uncommon, do occur with seasonal influenza with an estimated average of approximately 92 influenza-related pediatric deaths each year in the United States. Some deaths in children have been associated with co-infection with influenza andStaphylococcus aureus, particularly methicillin resistant S. aureus (MRSA).
Symptoms of severe disease may include:
- Altered mental status
- Extreme irritability
Treatment and prevention of swine flu
No vaccine is currently available to prevent S-OIV infection and it is thought unlikely that seasonal influenza vaccine will provide protection against this new virus. While not a substitute for a vaccine, a number of other interventions may be used to decrease the risk of infection and possible complications from S-OIV infection in children.
Influenza antiviral medications for use in children age 1 year and older
Antiviral treatment with oseltamivir or zanamivir is recommended for children with confirmed or probable S-OIV infection. See www.cdc.gov/swineflu/casedef_swineflu.htm for case definitions. Empiric antiviral treatment is also recommended for children with suspected cases of swine influenza A (H1N1) virus infection, especially those with severe illness. Antiviral treatment with zanamivir or oseltamivir should be initiated as soon as possible after the onset of symptoms. Evidence for benefits from treatment in studies of seasonal influenza is strongest when treatment is started within 48 hours of illness onset. However, some studies of treatment of seasonal influenza have indicated benefit, including reductions in mortality or duration of hospitalization even for patients whose treatment was started more than 48 hours after illness onset. Recommended duration of treatment is five days. Recommendations for use of antivirals may change as data on antiviral effectiveness, side effects and antiviral susceptibilities become available. Antiviral doses recommended for treatment of S-OIV infection in children 1 year of age or older are the same as those recommended for seasonal influenza (Table 1).Table 1. Recommended doses of zanamivir and oseltamivir antiviral medications for the treatment and prevention of influenza in children 1-18 years-old
|Antiviral agent||Age group (yrs)|
|Zanamivir*||Treatment, influenza A and B||N/A†||10 mg (2 inhalations) twice daily||10 mg (2 inhalations) twice daily||10 mg (2 inhalations) twice daily|
|Chemoprophylaxis, influenza A and B|| Ages 1-4|
| Ages 5-9|
10 mg (2 inhalations) once daily
|10 mg (2 inhalations) once daily||10 mg (2 inhalations) once daily|
|Oseltamivir||Treatment†, influenza A and B||Dose varies by child's weight§||Dose varies by child's weight§||Dose varies by child's weight§||75 mg twice daily|
|Chemoprophylaxis, influenza A and B||Dose varies by child's weight¶||Dose varies by child's weight¶||Dose varies by child's weight¶||75 mg/day|
|Duration of Treatment||Treatment||Recommended duration for antiviral treatment is 5 days.|
|Chemoprophylaxis||Recommended duration is 10 days after the last known exposure.|
Children Younger than 1 Year of Age
Children less than one year of age are at higher risk for complications associated with seasonal human influenza virus infections compared to older children, and the risk of influenza complications is especially high for children less than 6 months of age. The characteristics of human infections with S-OIV are still being studied, and it is not known whether infants are at higher risk for complications associated with S-OIV infection compared to older children. However, children less than 1 year old are known to be at increased risk of complications from seasonal influenza infection and during previous pandemics. Limited safety data on the use of oseltamivir (or zanamivir) is available from children less than one year of age, and oseltamivir is not licensed for use in children less than 1 year old. Available data comes from use of oseltamivir for treatment of seasonal influenza. However, these data suggest that severe adverse events are rare, and the Infectious Diseases Society of America recently noted that “… limited retrospective data on the safety and efficacy of oseltamivir in this young age group have not demonstrated age-specific drug-attributable toxicities to date.”.
Because infants typically have higher rates of morbidity and mortality from influenza compared to healthy older children, infants with S-OIV infections may benefit from treatment using oseltamivir. Oseltamivir use for children less than 1 year old was recently approved by the FDA under an Emergency Use Authorization (EUA), and dosing for these children is age-based. (Table 2).
Table 2. Recommended doses of oseltamivir antiviral medication for the treatment of S-OIV influenza for children less than 1 year of age.
|Age||Recommended treatment dose for 5 days|
|<3 months||12 mg twice daily|
|3-5 months||20mg twice daily|
|6-11 months||25 mg twice daily|
Use of fever-reducing medications in children
Aspirin or aspirin-containing products (e.g. bismuth subsalicylate – Pepto Bismol) should not be administered to any confirmed or suspected ill case of swine influenza A (H1N1) virus infection aged 18 years old and younger due to the risk of Reye syndrome. For relief of fever, other anti-pyretic medications are recommended such as acetaminophen or non steroidal anti-inflammatory drugs.
For antiviral chemoprophylaxis of S-OIV infection, either oseltamivir or zanamivir are recommended for children 1 year of age or older (Table 1). Oseltamivir can be used for chemoprophylaxis under the EUA for children less than 1 year-old (Table 3). Under this EUA, chemoprophylaxis is not recommended for infants less than 3 months old unless the situation is judged to be critical. Duration of antiviral chemoprophylaxis post-exposure is 10 days after the last known exposure to an ill confirmed case of swine influenza A (H1N1) virus infection. For emem Posted via email from wholefamilyjoy's posterous